One-Dimensional Modeling of Multiple Scattering in the Upper Inner Core: Depth Extent of a Scattering Region in the Eastern Hemisphere

Satoru Tanaka

doi:10.1007/s12583-013-0366-6

Volume 24 Issue 5

Oct 2013

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Journal of Earth Science > 2013 > 24(5): 706-715.

Satoru Tanaka. One-Dimensional Modeling of Multiple Scattering in the Upper Inner Core: Depth Extent of a Scattering Region in the Eastern Hemisphere. Journal of Earth Science, 2013, 24(5): 706-715. doi: 10.1007/s12583-013-0366-6

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Satoru Tanaka. One-Dimensional Modeling of Multiple Scattering in the Upper Inner Core: Depth Extent of a Scattering Region in the Eastern Hemisphere. Journal of Earth Science, 2013, 24(5): 706-715. doi: 10.1007/s12583-013-0366-6

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One-Dimensional Modeling of Multiple Scattering in the Upper Inner Core: Depth Extent of a Scattering Region in the Eastern Hemisphere

doi: 10.1007/s12583-013-0366-6

Satoru Tanaka^,

Institute for Research on Earth Evolution, Japan Agency for Marine-Earth Science and Technology, Yokosuka, 237-0061, Japan

Funds:

the Japan Society for the Promotion of Science (JSPS) KAKENHI 21340132

More Information

Corresponding author: Satoru Tanaka, stan@jamstec.go.jp
Received Date: 23 Nov 2012
Accepted Date: 04 Mar 2013
Publish Date: 01 Oct 2013

Abstract

Abstract

Attenuation of PKP(DF) in the Eastern Hemisphere is examined in terms of multiple scattering to simultaneously explain a puzzling relationship, a relatively fast velocity anomaly corresponding to strong attenuation. Reflectivity synthetics with one-dimensional random velocity fluctuations are compared with observations of PKP(DF)/PKP(Cdiff) amplitude ratios and differential travel times of PKP(Cdiff)-PKP(DF) for the equatorial paths. A Gaussian distribution of P-wave velocity fluctuations with the standard deviations of 5%, 6%, and 7% in the uppermost 200 km of the inner core is superimposed on the velocity structure that is slightly faster than the typical structure in the Eastern Hemisphere, which is likely to explain both the travel time and amplitude data as far as only the one-dimensional structure is considered. Further examinations of the statistic characteristic of scatterer distribution in two and three-dimensions are required to obtain a realistic conclusion.
- seismology,
- the inner core,
- attenuation,
- scattering

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References(35)

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One-Dimensional Modeling of Multiple Scattering in the Upper Inner Core: Depth Extent of a Scattering Region in the Eastern Hemisphere

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